From 9a0c032825e073e002ee80cf2577431d7296a7f7 Mon Sep 17 00:00:00 2001
From: Julien Thierry <julien.thierry@arm.com>
Date: Tue, 28 Aug 2018 16:51:15 +0100
Subject: [PATCH] arm64: Use daifflag_restore after bp_hardening
For EL0 entries requiring bp_hardening, daif status is kept at
DAIF_PROCCTX_NOIRQ until after hardening has been done. Then interrupts
are enabled through local_irq_enable().
Before using local_irq_* functions, daifflags should be properly restored
to a state where IRQs are enabled.
Enable IRQs by restoring DAIF_PROCCTX state after bp hardening.
Acked-by: James Morse <james.morse@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---
arch/arm64/mm/fault.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 1aa487a37a0a8..d0e638ef3af62 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -37,6 +37,7 @@
#include <asm/cmpxchg.h>
#include <asm/cpufeature.h>
#include <asm/exception.h>
+#include <asm/daifflags.h>
#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/sysreg.h>
@@ -776,7 +777,7 @@ asmlinkage void __exception do_el0_ia_bp_hardening(unsigned long addr,
if (addr > TASK_SIZE)
arm64_apply_bp_hardening();
- local_irq_enable();
+ local_daif_restore(DAIF_PROCCTX);
do_mem_abort(addr, esr, regs);
}
@@ -790,7 +791,7 @@ asmlinkage void __exception do_sp_pc_abort(unsigned long addr,
if (user_mode(regs)) {
if (instruction_pointer(regs) > TASK_SIZE)
arm64_apply_bp_hardening();
- local_irq_enable();
+ local_daif_restore(DAIF_PROCCTX);
}
clear_siginfo(&info);
--
2.30.2